The present invention relates generally to apparatus for processing products such as food and other products requiring heating or cooling and mixing, and more particularly to a processing vessel having a novel metering/mixing auger assembly associated therewith.
In preparing many types of products, a relatively large batch of a base constituent is first prepared in a mixing vessel capable of heating or cooling the base constituent during mixing. The base batch is then removed from the vessel and one or additional constituents are mixed with the base batch to create desired characteristics in the final product, such as a particular taste or density characteristic. For example, in making certain food products, a base batch is first prepared in a cooking and mixing vessel, and thereafter removed and an additive, such as baking soda, is mixed with the base batch in a controlled manner so that liberated gas is entrained in the mixture to obtain a desired density or softness characteristic in the final product. When forming products in this manner, the apparatus and technique for introducing the additive constituent, such as baking soda in the case of food products, into the base constituent batch must be capable of precisely metering the additive into the base batch. The apparatus must also insure uniform mixing and accommodate expansion of the base batch in instances where the additive gasifies the mixture.